Cast-off for wax-thread sewing-machines



No. 416,841. Patented Dec. 10, 1889.

' UNITED STATES.

PATENT ()FFICE.

JAMES H. JACOBS, OF BROCKTON, MASSACHUSETTS.

CAST-OFF FOR WAX-THREAD, SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 416,841, dated December 10, 1889.

Application filed September 14, 1889. Serial No. 323,943. (No model.)

To all whom it may concern.-

Be it known that I, JAMES H. JACOBS, of Brockton, in the county of Plymouth and State of Massachusetts, have invented a new and useful Improvement in Sewing-Machines, of which the following, taken in connection with theaccompanying drawings, is a specification.

My invention relates to improvements in sewing-machines in which an awl operates in conjunction with a barbed needle and a cast-off.

The object of my improvement is to provide a positive stop for the cast-off when in its highest position in the process of sewing, instead of causing it to be held up by the friction of the cast-off bar on the post in which it moves, as has been the caseprior to my invention; also, by eliminating this friction of the bar upon the post a very considerable saving of power is made. I attain these objects by the mechanism illustrated in the ac companying drawings, in which Figure 1 represents a perspective view of a post, needle-bar, and cast-off barfitted with my stop attachment. Fig. 2 represents a front view of the same.

Similar letters refer to similar parts throughout the drawings.

The post A constitutes the frame in which the needle-bar B and the cast-off bar 0 move up and down.

D is the needle-bar block, fastened securely to the needle-bar B.

E is the lower, and E the upper, cast-0E- bar block, both fastened to the cast-off bar.

F is the needle, and G the cast-0E.

H is the latch for catching the lowercastoff-bar block E. The latch is held in position by the spring K, and is pivoted atL by astud and nut. The latch is further held in position by the piece M, under which it moves easily backward and forward a sufficient distance to engage and disengage the lower castoff-bar block. The piece M is fastened by screws to the post A at N.

-O is the needle-bar-block stud, operated by suitable means in the sewing-machine.

P is a cam on the needle-bar block, which acts on the latch Hand throws it out to release the cast-off bar.

The operation of my invention is as follows:

By this means the cast-off bar has been imbreaks.

When the needle-bar B is carried to its highest point, as shown in Fig. 1, it carries with it its block D, and by means of its contact with the upper cast-otf-bar block E carries the cast-off G to its highest point. My latch H is so arranged as to catch the lower eastoff-bar block E and hold the cast-off at its highest point, as shown in Fig. 1. When the needle-bar descends through the work, carrying with it a loop of thread, the cast-off is held firmly in its place by my latch H, so that the downward motion of the needle will not move the cast-off until the latch H is disengaged from the lower cast-off-bar block E by the cam P acting on the latch H to throw it out, as in Fig. 2. It is necessary that the cast-01f should not be lowered from its posi-. tion immediately under the piece to be sewed until the barb of the needle has descended from its position as shown in Fig.1 to its position as shown in Fig. 2, or below the top of the cast-off. Otherwise the loop of thread which the cast-off is intended to hold 01f or castoff from the needle will draw up to the needle, slip by the cast-off, and enter the barb of the needle as the needle descends, forming a second loop under the barb in addition to the proper loop with which the needle is descending, and when this happens the needle or thread, or both, will be broken.

Prior to my invention the cast-off has been held at its highest point during the descent of the needle by pressure by a spring or otherwise upon the cast-off bar pressing it against the post in which it moves, and thus byfriction preventing it falling or being drawn down by its contact with the descending needle.

perfectly and insecurely held, and by the wearing of the parts under the friction and by the friction of the descending needle upon it the cast-off bar has been improperly lowcred when it should remain stationary. The thread and needle have thus been broken by reason of the slipping down of the cast-ofi. In other words, when the cast-off is lowered from its highest position before the barb of the needle has been closed by it the loop that should be cast olf the needle draws into the barb of the needle and the thread or needle In my invention the slipping down of the cast-off is impossible. When the cast- 0ft bar is at its highest point, the latch I-Lunder the pressure of the spring K, engages its block E. The needle-bar with its block descends from its position as shown in Fig. 1 to its position in Fig. 2, and then by means of the cam P releases the cast-ofiE-bar block, which moves downward with the needle bar block carrying the cast-off. The needle-bar with its block then moves upward, and striking the upper cast-off-bar block E carries the oast-oif upward till the lower cast-offibar block is engaged by the latch IL What I claim, and desire to secure by Letters Patent, is-

The combination, in a sewing-machine, of a post having a needle-bar and cast-off bar, with a latch operated by a spring and adapted to engage the cast-01f bar, and a cam on the needle-bar to throw out the latch, substantially as described.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, on this 11th day of Septemher, A. D. 1889.

JAMES H. JACOBS. Witnesses:

WARREN A. REED, CHARLES L. PIERCE. 

